Hi P-Fan1
You state your ideas very clearly - here's a rough analogy. Say you're flying single-engine fixed-wing and taking off from a 10-mile long salt flat. Would you do a maximum-angle-of-climb departure at a minimum airspeed, or would you let the airspeed come up strongly before you do a more "normal" takeoff.
Would you want to be 50' over the ground at 65kt hanging off the engine in a plank at almost-stall, when instead you can be in a nice 80 kt climb where if the prop stops you can just fly down instead of falling? Of course not. Now if there were 100' trees at the end of a 2,000' runway, different story.
In the helo, it's not about the strain on the engine (directly), it's about the pitch and resulting induced drag. If your engine stops while you are pulling a lot of pitch, you will lose a lot of RPM right now. Sure you can get the collective down quick, but meanwhile, even Johnny Lightning's RRPM will be in the bottom of the green. So there you are, waiting for the autorotative airflow to start so you can regain that RPM you so desperately need because it's all you're gonna have to cushion your landing, 'cause without solid forward airspeed, your flare won't do a thing.
Yep, they're helicopters, and in them we do helicoptery things. But the less power and more airspeed you are using in a departure (or approach), within the bounds of terrain, the mission you are accomplishing, and the H/V curve, the more options you will have if the fire goes out.
I agree with you though - it isn't going to be a TBO issue either way!